On Thu, May 03, 2018 at 01:55:03PM +0300, Ville Syrjälä wrote: > On Thu, May 03, 2018 at 11:24:59AM +0200, Daniel Vetter wrote: > > On Thu, May 03, 2018 at 11:19:32AM +0530, Satendra Singh Thakur wrote: > > > In the func drm_atomic_set_crtc_for_plane, with the current code, > > > if crtc of the plane_state and crtc passed as argument to the func > > > are same, entire func will executed in vein. > > > It will get state of crtc and clear and set the bits in plane_mask. > > > All these steps are not required for same old crtc. > > > Ideally, we should do nothing in this case, this patch handles the same, > > > and causes the program to return without doing anything in such scenario. > > > > > > Signed-off-by: Satendra Singh Thakur <satendra.t@xxxxxxxxxxx> > > > Cc: Madhur Verma <madhur.verma@xxxxxxxxxxx> > > > Cc: Hemanshu Srivastava <hemanshu.s@xxxxxxxxxxx> > > > --- > > > drivers/gpu/drm/drm_atomic.c | 4 +++- > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > > > index 7d25c42..5bd3365 100644 > > > --- a/drivers/gpu/drm/drm_atomic.c > > > +++ b/drivers/gpu/drm/drm_atomic.c > > > @@ -1421,7 +1421,9 @@ drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state, > > > { > > > struct drm_plane *plane = plane_state->plane; > > > struct drm_crtc_state *crtc_state; > > > - > > > + /* Nothing to do for same crtc*/ > > > + if (plane_state->crtc == crtc) > > > + return 0; > > > > I didn't do this (both here and in the set_crtc_for_connector functions) > > because the overhead is probably way down in the noise compared to the > > overall atomic commit machinery. Do you really see this as a hotpath? > > drm_atomic_set_crtc_for_connector() actually has this since commit > e2d800a3ce1b ("drm: Avoid connector reference imbalance on error path") Ok, applied for consistency. Thanks for the patch. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel